Method for preparing oxycodone

Abstract

A method for the preparation of oxycodone, and salts thereof, from codeine comprising oxidation of codeine to codeinone, formation of an dienolsilyl ether congener of codeinone in strong amine base, oxidation of the dienolsilyl ether congener using peracetic acid, and hydrogenation of the resulting 14-hydroxycodeinone product.

What is claimed is:  
     
       1. A method for forming a dienol silyl ether selected from the group having the formula:                    
       wherein R 1  is alkyl or acyl, R 2  is lower alkyl, allyl, or lower alkyl substituted by cycloalkyl, and R 3  is an alkyl or aryl group and the three R 3  groups are the same or different  
       which comprises the steps of:  
       reacting an morphinan-6-one selected from the group having the formula:                    
       wherein R 1  and R 2  are as defined above, with an organosilyl compound having the formula 
       
         
           R 3   3 SiX  
         
       
       wherein R 3  is as defined above and X is a leaving group selected from imidazole, mesylate, tosylate or halogen,  
       in the presence of a strong amine base and an aprotic solvent.  
     
     
       2. The method of claim  1  wherein the strong amine base is a diazabicylco-base. 
     
     
       3. The method of claim  2  wherein the diazabicyclo-base is selected from the group consisting of: DBU (1,8-Diazabicyclo[5.4.0. ]undec-7-ene) and DBN (1,5-Diazabicyclo[4.3.0]non-5-ene). 
     
     
       4. The method of claim  1  wherein R 3  is C 1 -C 4  alkyl or phenyl. 
     
     
       5. The method of claim  1  wherein X is chloride.